Return trap



May 21, 1929. F. M. WEBSTER RETURN TRA P Filed Nov. 16, 192e l i I lll',

Patented May 21, 1929.v

UNITED STA TES-PATENT OFFICE.

FRANK M. WEBSTER, O F WELLESLEY FARMS, MASSACHUSETTS, ASSIGNOR '.lO W. D.

CASHIN C0., F BOSTON, MASSACHUSETTS, A CORPORATION 0F MASSACHUSETTS.

RETURN TRAP.

Application led November 1G, 1926. Serial No'. 148,721.

This invention relates to traps of the type used in steam and vapor heating systems for accumulating the condensation from the re turn mains and intermittently releasing said condensation for return tothe boiler.

It is the chief object of theinvent'ion to devise a trap of this, character which will be usually reliable in operation, while at the same time being simple in construction'and economical to manufacture.

The nature of the invention will be readily understood from the following description when read in connection with the accompanying drawings, and the novel features will be particularly pointed out in the appended claims. Y a

In the drawings, Y v y Figure 1 is a vertical, cross-sectional view showing a return trapv constructed in accordance with this invention; l f

Y Fig. 2 is a fragmentary view similar to F ig. 1, but showing certain parts of the lvalve operating mechanism in a different position; and

Fig. 3 is a cross-sectional view at right anglesto Fig. 2 showing, in elevation, the valve operating mechanism whichpappears in the latter figure.

The construction'shown comprises a tank or casing 1, preferably equippedwith the usual gage glass 2. Tapped into the lower end of this casing is a pipe 3 which usually is connected to the return line between two check valves arranged to permit the water condensing in the heating or other system to flow into the trap casing 1, and also to How from this trap into the boiler, but serving to revent any reverse flow.y

Folted to the top ofthe trap casing 1 is a supplemental or valve casing 4 to which a steam line 5 leading from the boiler is connected. A vent pipe 6 leads from this casing. The admission of steam to the trap or the opening thereof tothe vent is controlled by a valve 7 s lidably mountedv in valve seat members 8 and 9 which are in alinement with each other. f

The operating mechanism for this valve comprisesa float 10 mounted on the end of a rod 11 which is fulorumed at 13 on a depending arm or bracket 4 formed integral with the valve casing 4. The float lever is connected by a link 12 to the lower end of a loop-shaped lever or toggle link 14 which is fulcrumed at 15 in the upper end of the tering-the casing 1 at this time.

casing 4. Pivoted at 16 on this lever and mounted Abetween the arms thereof is a yokeshaped link 17, the legsof which are pinched together near the upper end of this part, this end of the link extending through a slot formed in the cent-ral part of the valve 7.

Located between the two arms of the link 17 and pivoted kto them at 18 is a short plate 19, and the upper end of a coiled spring 2O is connected to the lower edge of this plate, the opposite end of said spring being fastened by an eye bolt 21 to a part of the bracket 4. This whole structure including the valve element and-its operating mechanism may be regarded as a valve unit.

In installing this trap it is generally located adjacent to the boiler and atleast several inches above the maximum water line in the boiler. Assuming that the .parts are in the positions shown in Fig. 1, water condensing in the heating system will flow into the tank or casing 1 through the-pipe 3, the air displaced by the water finding its way out'of the tank through the venty 6. At this time the rightvhand valve member of the recip-k rocating valve 7 is held'against its seat in the part 8 by means of the spring 20 operating through the toggle mechanism and holding it in its broken or collapsed position. Steam therefore is prevented vfrom en- As the water level rises in the casing, the float 10 will rise with it, and this motion will be transmitted to the toggle link 14, swinging it toward the right. This movement has both the effect of straightening the toggle and also of tensioning the spring 20 since the straightening movement of the tog le will lift the point 18, and consequently t e plate 19, as will be evident from an inspection of Fig. 1. Such a straightening motion of the toggle, however, does not produce any movement of the valve 7 due tothe lost motion between the toggle mechanism and the valve. But the instant that the toggle mechanism is moved slightly past its straightened position, thespring 2O snaps the toggle into its collapsed position opposite to the position in which it is shownin Fig. 1. During this' movement the plate 19 is thrownagainst the left hand edge, Figs. 1 and 2, of the slot in which it is positioned in the valve 7 and slides this valve with a snap movement into the position shown in Fig. 2 where its left hand valve member closes the vent. Steam new flows freely i'rom the pipe 5 `into the tank l. Inasmuch as the tank islocated "above the Water level in the boiler, and since the steam `pressnresin the boiler and tank 1 now are eqnalized, the Water will tlovv by gravity out of the tank and into the boiler. This Will produce a lowering movement ot the float l() which Will gradually straighten the toggle mechanism again. until `it A.has moved slightly past its straightened position, When tliespring Will again snap the toggle into itscollapsed position, as shown in Fig. l, thus shutting oli the flow ot steam into the -tank and opening the Itank to the vent. This cycle of operations Will be repeated indefinitely.

The movements ot' the valve are thus ettected positively, and at the same time the construction is very simple and economical to manufacture. It it should be necessary to make repairs, the valve casing et can be removed, carrying the valves and the float with it. v

W'hile I haveherein shown and described the best 4tmb(aliment oi my invention that I have so tar devised, it Will be understood that the invention-may be embodied in other forms without departing 'jrom the spirit or scope thereof.

`Having-thus described my invention, what I desire to claim as new is:

1. Ina return trap, the combination ot a casing `adapted `to hold Water, and a valve unit comprising a float in said casing, a vent lea-ding from said casing, a steam inlet leading into said casing, a slidable vaive having two valve members for controlling said vent and inlet,'respectively, a toggle mechanism associated With said valve tor sliding it from one lposition to another, a spring tending to collapse-said toggle, and a float in saivdcasing connected with said toggle mechanism and arranged to straighten it, said toggle and valve being arranged to permitthe straightening of the toggle Without moving said valve members off their seats.

2. In a return trap, the combination of a casing adapted to holdwvater, and a valve unit comprising a iloat in said casing, a vent leading trom said casing, a steam inletleading into said casing, a toggle link pivoted in said casing, a float arranged to move said link, a second toggle link pivoted at one end to the iirst link, a spring connected With the opposite end of the second link and arranged to be tensioned by the straightening of the toggle, and valveimeans arranged to be operated by said toggle and controlling said vent and inlet, said toggle and valve means being arranged to permit the straightening of the toggle Wit-hout operating said valve means.

3. In a return trap, the combination of a casing adapted to hold Water, and a valve unit comprising a float in said casing, a vent leading trom said casing, a steam inlet leadingfinto said casing, said vent and inlet being in alinementwith each other, a reciprocating valve guided in said vent and inlet and-having 'a valve member operative to close the vent when the valve is inoperative position and another valve member for closing lthe inlet vvhen the valveV is in its opposite position, a float in said casing, a toggle mechanism arranged to be straightened by said float and serving to `move said valve from one of its operative positions to the other, and a spring associated with said toggle for giving ita snap-movementV from one position to another,-saidtoggle and valve being arranged topermit-the straightening of the `toggle Without operating-the valve.

4. 4In a return trap, thecombinationof a casing adapted to hold Water, and a valve unit comprising a iioat insaid casing, a vent leading i'rom saidcasing, a steam-inlet `leading into said casing, a Water inlet leading-into said-casing, valve members controlling said vent and inlet, a toggle mechanism `for operating said members, a spring arranged to `be tensioned by the straightening-ofthe toggle and-operative to collapse kthe toggle `With a snap movement, said valve members being arranged to be operated by said toggle mechanism during the snap movement'only of said mechanism, and said mechanism `being aetuated by said float.

5. In a return trap,the combination of a casing adapted to held Water, and a -valve unit comprising a float in said casing, a vent leading trom said casing, a steam inlet leading into said casing, a toggle llink pivoted in said casing, a float arranged to -move said link, a second toggle link pivoted at one `end to an intermediate point on the Iiirstlink, a member pivotedto the opposite-end 'of said second link, a spring connected at oneend to said member and arranged to be `tensioned by the straightening ot the toggle whereby said rspringrWill collapse the toggle Witha snap movement, 4and valve means `havinga lest motion connection with said member and arranged to be operated thereby during the snap movement only otthe toggle, said valve means controlling said vent and inlet.

6. In a return trap, thecombination of a casing adapted to hold Water, and a valve unit 'comprising float in said casing, a vent'leading from said-casing, a steam inlet leading into said casing, a toggle link pivoted in said casing,a iioat arranged `to move saidlink, a second toggle link pivoted at one end to an intermediate pointon the first link, a member pivoted to the opposite end kot said'second link, a spring connected'atone end tosaid member and arranged to be tensioned bythe straightening of the toggle whereby said spring Will collapse the toggle vvitha snap movement, a slidable valve having Va lost motion connection with said-member andarranged to be operated thereby during the snap movement only of the toggle'ineither direction, said slidable valve having valve elements controlling said vent and said inlet.

7. In a return trap, the combination of a main casing adapted to hold Water, and a valve unit comprising a float in said casing,

a vent leading from said casing, a steam inlety leadlng into said casing, valve members oontrolling said vent and inlet, a valve casing in Whlch said valve members are mounted, sald 10 valve Casing being removably secured to said main casing, a toggle mechanism for operating said valve members, and a float in said main easing for actuating said toggle mechanism, said toggle mechanism and float being supported on said valve casing for removal.

therewith from the main casing.

`In testimony whereof I have signed my name to this specification.

FRANK M. WEBSTER. 

